| Author |
Message |
![[Post New]](/templates/default/images/icon_minipost_new.gif) 14 May 2008 17:49:08 IST
|
|
|
the total no. of 5 digit numbers of different digits in which the digit in the middle is the largest
|
|
|
|
![[Post New]](/templates/default/images/icon_minipost_new.gif) 14 May 2008 17:57:19 IST
|
|
|
Is the ans 9c5(4!)+9c4(3)(3!).If it is correct,I will explain.
|
MAKING A MISTAKE IS HUMAN BUT REPEATING IT IS IDIOTIC. |
this reply: 0 points
(with 0 
in 0 votes ) [?]
|
|
You have to be logged on to rate
|
|
|
![[Post New]](/templates/default/images/icon_minipost_new.gif) 14 May 2008 18:10:36 IST
|
|
|
i dont know the real answer as the correct answer to the question given was NONE OF THESE
PLEASE GIVE YOUR APPROACH
|
this reply: 0 points
(with 0 
in 0 votes ) [?]
|
|
You have to be logged on to rate
|
|
|
![[Post New]](/templates/default/images/icon_minipost_new.gif) 14 May 2008 18:15:00 IST
|
|
|









|
__________________________________________________________________________________________________________
From J.R.R. Tolkien's 'The Lord of the Rings':
All that is gold does not glitter
Not all who wander are lost
The old that is strong does not wither,
Deep roots are not reached by frost.
From ashes a fire shall be woken
From shadows a light shall spring
Renewed shall be blade that's broken
The crown less again shall be king. |
this reply: 0 points
(with 0 
in 0 votes ) [?]
|
|
You have to be logged on to rate
|
|
|
![[Post New]](/templates/default/images/icon_minipost_new.gif) 14 May 2008 18:26:51 IST
|
|
|
There are two cases.One is the numbers without 0 and other is the numbers with 0.
WITHOUT 0:select 5 numbers from 1,2,....,9 in 9c5 ways and place the largest no. among them in the middle.The remaining 4 numbers can be arranged in 4! ways.
WITH 0:Select remaining 4 numbers from 1,2,...,9 in 9c4 ways and place the largest among them in the middle.Since 0 can't be placed in first position,the no. of ways of arranging 0 and remaining 3 no.s is not 4! but 3(3!).
Hence the ans is 9c5(4!)+9c4(3)(3!)=9c5(3!)(7)
|
MAKING A MISTAKE IS HUMAN BUT REPEATING IT IS IDIOTIC. |
this reply: 5 points
(with 1 
in 1 votes ) [?]
|
|
You have to be logged on to rate
|
|
|
|
|